Method of making a structural member



Nov. 21, 1961 E. MARTIN 3,009,509

FIG. 4 23 INVENTorc EDWARD MARTIN Nov. 21, 1961 E. MARTIN METHOD oRMAKING A STRUCTURAL MEMBER i5 Sheets-Sheet 3 Original Filed May 7, 1957INVENTORI EDWARD MARTIN BY M2 W j ATT'YS United States Patent Office3,009,509 Patented Nov. 2l, V1961 3,009,509 METHOD OF MAKING ASTRUCTURAL MEMBER Edward Martin, Chicago, Ill., assignor to Central FarmEquipment Company, Chicago, Ill., a partnership Original application May7, 1957, Ser. No. 657,643. Divided and this application May 22, 1958,Ser. No.

Z Claims. (Cl. 153-54) This invention relates to a method of making astructural panel member that may be used in multiple to form the wallsand/or roof of a trussless b-uilding, although other uses and purposesmay be apparent to one skilled in the art.

More specifically, the panel formed according to the present inventionis generally trough-shaped and arched longitudinally and provided withsmooth inner and outer surfaces.

This application is a division of my copending patent application SerialNumber 657,643, filed May 7, 1957, entitled Structural Member.

Heretofore, many panels of this type and configuration have beendeveloped, but in nearly all cases transverse corrugations or the likehave been formed in the panel in order to form the longitudinal arch inthe panel.

It has been found that these cross or transverse corrugations weaken thepanels.

Accordingly, it is an object of this invention to provide an improvedpanel which obviates the above difficulties, and which has smooth innerand outer surfaces.

Another object of this invention resides in the provision of a generallytrough-shaped and longitudinally arched panel having smooth inner andouter surfaces thereby greatly enhancing the strength and rigiditythereof.

Still another object of this invention is in the provision of agenerally trough-shaped and longitudinally arched structural panel,wherein the longitudinal arching may be accomplished without resortingto cross corrugations thereby giving a more durable and stronger panel.

A further object of this invention is to provide a method of making agenerally trough-shaped and longitudinally arched panel devoid of crosscorrugations.

Y' A still further object of this invention is in the provision of amethod of making a generally trough-shaped and longitudinally archedstructural panel having smooth inner and outer surfaces, wherein thearching of the panel is accomplished without forming any crosscorrugations therein thereby providing a stronger and more rigid anel.

p Another object of this invention resides in the provision of a blankfor forming a generally trough-shaped and longitudinally archedystructural panel having smooth inner and outer surfaces, wherein theblank is generally rectangular in shape with the middle areas of theopposite ends having portions removed therefrom so that when the panelhas been preformed and arched, the ends will be flush.

Other objects, features and advantages of the invention will be apparentfrom the following detailed disclosure, taken in conjunction with theaccompanying sheets of drawings wherein like reference numerals refer tolike parts, in which:

' FIG. 1 is a perspective view of a trussless building embodying thepresent invention;

FIG. 2 is a perspective view of a single arch of the building in FIG. 1illustrating the manner in which the panels embodying the presentinvention are secured in end-to-end relationship;

FIG. 3 is a perspective view of the structural panel embodying thepresent invention;

FIG. 4 is a broken top plan view of the blank utilized for fashioningthe panel of the present invention;

FIG. 5 is a perspective view of the blank in its preformed conditionprior to the longitudinal arching thereof;

FIG. 6 is a fragmentary longitudinal sectional view, taken substantiallyalong line 6-6 of FIG. 7, and illustrating the method of arching thepanel according to the invention;

FIG. 7 is a greatly enlarged transverse sectional view, takensubstantially along line 7-7 of FIG. 6; and

FIG. 8 is a modification of the invention.

The structural panel or member of the present invention is preferablymade of sheet steel or aluminum, although it may `be constructed of anyother type of suitable material such as plastic. When the panels aremade of plastic, it will be appreciated that the panels will then beconstructed by a molding process as is well known in the plastic fields.

This structural panel or member is generally transversely trough-shapedand longitudinally arched i-n such a manner that the inner and outersurfaces are completely smooth. The method of forming the panel includespreforming a blank and feeding the panel through successively spacedsets of coacting rollers arranged to gradually fashion the longitudinalarch in each panel. The panel is formed from a blank, substantiallyrectangular in shape and having portions removed from the opposite endsthereof so that when the panel is completely formed and arched, the endswill be ush.

Referring now more particularly to the drawings, there is illustratedherein a structural panel or member 10, FIG. 3, embodying the presentinvention. Each panel includes a center concavo-convex section 11 facingupwardly, outer concavo-convex sections 12-12 facing downwardlyextending from the upper edges of the center section, and inner andouter smooth surfaces 13 and 14. The outer sections 12 serve to provideconnecting portions for connecting a plurality of these panels insideby-side and e-nd-to-end relationship, when forming a building suchas the building 15 in FIG. 1, and accordingly are provided with aplurality of holes 16, FIG. 3, spaced therealong for receiving fastenersfor connecting the pan els together.

The building 15 in FIG. 1\, being formed by connecting a plurality ofpanels together in multiple, includes straight end Walls 17 formed froma sheathing or the like of any desirable material, and wherein a door 18may be arranged in one of the end Walls 17. Due to the rigidity andstrength embodied in each panel, and the combined rigidity and strengthof a plurality of panels secured together, the building 15 needs noadditional trusses, and is therefore of a trussless type. Actually, aplurality of the panels 10 secured together in end-to-end relationshipform an arch 19, FIG. 2, which not only serves as the walls and roof ofa building but also serves as an individual truss. For illustrating theinvention, the panel herein shown has a certain longitudinal arch, whichwill, when connected in end-to-end relationship with other panels toform the truss 19, form the truss having a center maximum height 20 anda maximum width 21 at the bottom. By changing the Ilongitudinal arch ofthe panel, the radius of curvature longitudinally of the panel will also4be changed and a building of a different height `and width may beconstructed. Accordingly, the amount of longitudinal arch to be providedin each panel may vary according to the demands of the user.

The panel o-f this invention is formed from a flat, generallyrectangularly shaped blank 22, FIG. 4, having opposed parallel sideedges 23-23. The opposed end edges are formed so that when fthe panelhas been preformed and longitudinally arched, the end edges will beflush or straight. To accomplish this, portions are cut away or removedfrom the middle areas 24 and the outer areas are convexly formed at 25.Thus, the middle areas 24 are concavely formed while the outer areas 25'are convexly formed. This is because the longitudinal radius ofcurvature is greater at the outer edges of the panel (the outer surfacesof the outer sections 12), and lesser at the inner surface of the centersection 11. Illustrating -this concept with the preformed but notlongitudinally arched member of FIG. 5, when the panel has beenlongitudinally arched, the longitudinal radius of curvature is greaterat the outer extremity 26 than at the inner extremity 27, and thisradius of curvature gradually increases from the value at the innerextremity 27 to the value at the outer extremity 26. Accordingly, inorder to have lthe opposite edges of the panel flush after thelongitudinal arching has been accomplished, the shortening of the outersections 12 due to the longitudinal arching is compensated by having thelengths in these areas greater in the blank as seen in FIG. 4. It willbe understood that when forming the panel from the blank 22, it willnecessarily be of metal such as sheet steel or sheet aluminum. Thus, inorder to form the parts on the panel having the longer or greaterlongitudinal radius of curvature, it is necessary that more metal bepresent to effect this formation, and therefore the shaping of theopposite ends of the 4blank 22 will accordingly provide the longitudinalarched panels with fiushed ends.

In the formation of the metal panel from the blank 22, the blank isinitially preformed to the shape as shown in FIG. to fashion thepreaformed member 28. This may be accomplished in a single stampingoperation or several stamping operations or by any other suitable methoddesired.

The next step of longitudinally arching the preformed panel 28 isextremely important in that the arching must be `accomplished in such amanner as to avoid the formation of any wrinkles or the like in thepanel which would obviously weaken the panel. Accordingly, as seen inFIGS. 6 and 7, the panel is fed through a series of spaced sets ofcoacting rollers. First, the outer sections 12 are introduced betweencoacting sets of outer rollers 29 and 30 one set for each outer section12, and being arranged in transversely spaced relation so that theyengage properly the opposing outer sections 12 as well as being arrangedalong one transverse plane. Each set of rollers includes an upper roller31 having a conrvexly shaped face and being mounted on a rotatablysupported shaft 32, and a lower roller 33 having a concavely shaped facecomplementary to the convex face of the upper roller 31, and beingmounted on a rotatably supported shaft 34.

The panel is fed through the rollers in the direction as indicated bythe arrow 35, FIG. 6, and any of the rollers may or may not be powerdriven.

Spaced from the first set of outer rollers 29 and 30 and positioned toreceive the center section 11 of the panel is a tirst set of innerrollers 36 including upper and lower rollers 37 and 38 havingrespectively complementary formed concave and convex faces. The upperroller 37 is supported on a rotatable shaft 39, while the lower roller38 is supported on a rotatable shaft 40. The sections of the panel aheadof the rst set of outer rollers 29 and 30 and the first set of innerrollers 36 will be straight. These sections are indicated respectivelyby the letters a. and c.

The outer sections 12 are then fed through a second set of outer rollers41 spaced from the lirst set of outer rollers and of the same type,while the center section 11 of the panel is fed through a second set ofinner rollers 42 which are spaced from the iirst set of inner rollers 36and of the same type. These second sets of rollers are arranged so thattangents extending from the bight (point of contact between coactingrollers) thereof will be displaced or spaced from tangents extendingfrom the bights of the rst sets of rollers to the extent that an archingof the panel will be effected by feeding them through the rollers. Thesections of the panel between the first and second sets of outer andinner rollers as indicated by the letters b and d will be slightlycurved, and the panel will be finally arched upon leaving the second setof rollers. Thus, the outer sets of rollers 29, 30, and 41 effect thearching of the outer sections 12, while the inner sets of rollers 36 and42 effect the arching of the center section 11, although all of therollers coact to effect the arching of the entire panel. An example ofthe relative distances between the rollers relative to the lengths ofthe panels would be where the panels are approximately l0 feet long, thedistance between the iirst set of outer rollers 29 and 30 and the lastset of inner rollers 42 is approximately 36 inches. Accordingly, thedistance between the first outer set of rollers and the second set ofinner rollers is about one-third the length of a panel.

Wrinkles, which would reduce the strength of a panel, -are avoided bylongitudinally arching a panel in accordance with the method of thepresent invention. The metal of the panel is worked as the panels arefed through the rollers, and since the metal panels are not heated, itmay be said that a cold working operation is performed on the panels inorder to effect a longitudinal arching thereof.

In FIG. 8 a modiiication of the invention is illustrated which differsfrom the embodiment of FIG. 3 only in that a panel 43 is arrangedbetween one of the upper edges of the center section 11 and one of theouter sections 12. In all other respects this panel is like that of theembodiment of FIG. 3 including the provision of having smooth outer andinner surfaces 13 and 14. This panel is also longitudinally arched andmay be arched by substantially the same type of roller arrangement asshown in FIGS. 6 and 7 except that for arching the panel 43 a pair ofcoacting rollers having cylindrical faces may be employed.

It will be undelstood that modifications and variations may be electedwithout departing from the scope of the novel concepts of the presentinvention, but it is understood -that this application is to be limitedonly by the scope of the appended claims.

The invention is hereby claimed as follows:

1. The method of making a transversely trough-like and longitudinallyarched structural panel having smooth inner and outer surfaces from aflat rectangular metal blank including preforming the blank to define apanel having a center concavo-convex section facing upwardly and outerconcavo-convex sections facing downwardly and extending from the upperedges of the center section, longitudinally arching said panel atambient temperature by feeding same through a series of rollersrotatable about axes parallel to each other comprising, feeding theouter sections between a rst set of transversely spaced outer coactingrollers, feeding lthe center section through a tirst set of innercoacting rollers spaced ahead of said first set of outer rollers,feeding the outer sections between a second successive set oftransversely spaced outer coacting rollers spaced -ahead of said rst setof inner rollers and positioned along a plane extending through thebight of said second set of outer rollers and tangent thereto angularlyintersecting a plane extending through the bight of said first set ofouter rollers and tangent thereto, and feeding said center sectionbetween a second successive set of inner coacting rollers spaced aheadof said second set of outer rollers and positioned along a planeextending through the bight of said second set of inner rollers andtangent thereto angularly displaced from a plane extending through thebight of said first set of inner rollers and tangent thereto, wherebyall said rollers gradually effect a cold working of the metal panel tolongitudinally arch the panel.

2. The method of making a transversely trough-like and longitudinallyarched structural panel having smooth inner and outer surfaces from aflat rectangular metal blank including prefornu'ng the blank to define apanel having a center concavo-convex section facing upwardly and outerconcavo-convex sections facing downwardly and -extending from the upperedges of the center section, longitudinally arching said panel atambient temperature by feeding same through a series of rollersrotatable yabout axe-s parallel to each other comprising, feeding theouter sections between la rst set of transversely spaced outer coaotingrollers, feeding the center section through `a first set of innercoacting rollers spaced ahead of said rst set of outer rollers, feedingthe outer sections between a second successive set of transverselyspaced outer coasting rollers spaced `ahead of said rst set of innerrollers and positioned along a plane extending through the bight of saidsecond set of outer rollers and tangent thereto angularly intersecting aplane extending through vthe bight of said rst set of outer rollers andtangent thereto, and feeding said center section between a secondsuccessive set of inner coacting rollers spaced ahead of said second setof outer rollers and positioned along a plane extending through thebight of said second set of inner rollers and tangent thereto angularlydisplaced from a plane extending through the bight of said first set ofinner rollers Iand tangent lthereto, whereby all said rollers graduallyeffect `a cold working of the metal panel to longitudinally arch thepanel, the distance between said rst set of outer rollers and `saidsecond set of inner rollers being about one-third the length of thepanel.

References Cited in the tile of this patent UNITED STATES PATENTS 37,308Seely Jan. 6, 1863 774,108 Richardson N'ov. 1, 1904 1,068,893 Green July29, 1913 1,158,484 Groehn Nov. 2, 1915 1,793,351 Bell Feb. 17, 19312,206,068 Yoder July 2, 1940 2,279,197 Hoell Apr. 7, 1942 2,342,026Watter Feb. 15, 1944 2,674,294 Ekberg Apr. 6, 1954

